1、Designation: D 3883 04Standard Test Methods forYarn Crimp and Yarn Take-up in Woven Fabrics1This standard is issued under the fixed designation D 3883; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A nu
2、mber in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the determination of the rela-tionship between the length of a piece of fabric and the lengthof the yarn in the
3、fabric by measurement of the yarn crimp andyarn take-up.1.2 This test method applies to woven fabrics.1.3 The values stated in either SI or inch-pound units are tobe regarded separately as standard. Within the text, theinch-pound units are shown in parentheses. The values statedin each system are no
4、t exact equivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two systems may result in nonconformancewith the specification.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibili
5、ty of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 123 Terminology Relating to TextilesD 1776 Practice for Conditioning and Testing TextilesD 2904 P
6、ractice for Interlaboratory Testing of a Textile TestMethod that Produces Normally Distributed DataD 2906 Practice forStatements on Precision and Bias forTextilesD 4849 Terminology Relating to Yarns and FibersD 4850 Terminology Relating to Fabric3. Terminology3.1 For definition of textile terms used
7、 in this test method:bench marks, refer to Terminology D 4849.3.2 For definitions of textile terms used in this test method:yarn crimp and yarn take-up, refer to Terminology D 4850.3.3 For definitions of other textile terms used in this testmethod, refer to Terminology D 123.4. Summary of Test Metho
8、d4.1 Bench marks are placed on a length of a yarn as it liesin a woven fabric. The distance between the bench marks ismeasured. The yarn is removed from the fabric, straightened byapplying suitable tension, and the distance between the benchmarks is remeasured. Yarn crimp is the change in lengthexpr
9、essed as a percent and based on the in-fabric distance. Yarntake-up is the change in length expressed as a percent andbased on the out-of-fabric distance.5. Significance and Use5.1 The relationship of the length of a piece of fabric and thelength of yarn in the fabric can be determined accurately on
10、lybe measuring the length of yarn entering the loom and thelength of fabric made from that particular length of yarn. Inmost cases, however, the determination must of necessity bemade on a woven fabric by measuring the length of yarnremoved from a measured length of fabric, thus introducingcertain v
11、ariations that will influence the accuracy of the test.Yarn removed from the woven fabric contains undulations orwaves that have been introduced by the weaving process. Heat,moisture, and mechanical shrinkage on subsequent finishingoperations may accentuate these undulations, and in all prob-ability
12、, increase the force to pull them out and straighten theyarn. In order to accurately measure the length of the yarn afterthe removal of the crimp, these undulations must be pulled outwithout elongating the yarn. In some cases, the minimum forcenecessary to straighten the yarn will cause a certain am
13、ount ofthe elongation to take place, thus increasing the length of theyarn. Also, stresses imposed upon the yarn during the weavingprocess may have been sufficient to stretch the yarn beyond itselastic limit, again increasing its length. It is recognized thatdetermination made by measuring length of
14、 yarn removed froma measured length of fabric may tend to give crimp values thatare somewhat higher than the crimp in the yarn as it lay in thefabric. In the case of fabrics made from yarns that exhibitdifferential shrinkage, or yarns of widely different count, or1This test method is under the juris
15、diction of ASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D13.59 on Fabric Test Methods,General.Current edition approved Dec. 1, 2004. Published January 2005. Originallyapproved in 1980. Last previous edition approved in 1999 as D 3883 99.2For referenced ASTM standard
16、s, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 1
17、9428-2959, United States.yarns woven at different tensions, the crimp of each type ofyarn in the fabric must be determined and reported separately.5.2 This test method can be used for acceptance testing ofcommercial shipments but comparisons should be made withcaution because information on estimate
18、s of between-laboratory precision is limited as noted in 13.1.5.2.1 If there are differences of practical significance be-tween reported test results for two laboratories (or more),comparative tests should be performed to determine if their isa statistical bias between them, using competent statisti
19、calassistance. As a minimum, ensure the test samples to be usedare as homogeneous as possible, are drawn from the materialfrom which the disparate test results were obtained, and arerandomly assigned in equal numbers to each laboratory fortesting. The test results from the two laboratories should be
20、compared using a statistical test for unpaired data, at aprobability level chosen prior to the testing series. If a bias isfound, either its cause must be found and corrected, or futuretest results for that material must be adjusted in considerationof the known bias.6. Apparatus6.1 Suitable Device3,
21、 for straightening the yarn throughapplication of horizontal or vertical tension, having two yarnsupport surfaces or two clamps, the distance between whichmay be altered in order to apply the needed tension.6.2 Suitable Marking Device, for marking bench marks onthe yarn specimen.7. Sampling and Test
22、 Specimens7.1 Primary Sampling UnitConsider rolls of fabric orfabric components of fabricated systems to be the primarysampling unit, as applicable.7.2 Laboratory Sampling UnitAs a laboratory samplingunit take from rolls two pieces of fabric, full width, each 375mm (15 in.) in length along the selva
23、ge (machine direction)after removing a first 1-mm (1-yd) length. For fabric compo-nents of fabricated systems use the entire system.7.3 Test SpecimensFrom each laboratory sampling unit,as required for each the warpwise and fillingwise directions,take ten test specimens, each 300 mm (14 in.) long as
24、directionin Section 9. Consider the long direction as the direction of test.7.3.1 For fabric widths 125-mm (5-in.) or more, take nospecimen closer than 25-mm (1-in.) from the selvage edge.7.3.2 For fabric widths less than 125-mm (5-in.), use theentire width for specimens.7.3.3 Ensure specimens are f
25、ree of folds, creases, orwrinkles. Avoid getting oil, water, grease, etc., on the speci-mens when handling.7.3.4 If the fabric has a pattern, ensure that the specimensare a representative sampling of the pattern.8. Conditioning8.1 Condition the specimens by bringing them to approxi-mate moisture equ
26、ilibrium in the standard atmosphere forconditioning textiles as directed in Practice D 1776.9. Preparation of Test Apparatus and Calibration9.1 Set-up procedures for machines from different manufac-turers may vary. Prepare and verify calibration of the testingdevice as directed in the manufacturers
27、instructions.10. Procedure10.1 Test the specimens in the standard atmosphere fortesting textiles, as described in Practice D 1776.10.2 Handle the test specimens carefully to avoid alteringthe natural state of the material.10.3 Test ten specimens from the warpwise direction or tenspecimens from the f
28、illingwise direction, or both, as required ina material specification or contact order.10.4 Using the marking device, make two lines (benchmarks) 250 mm (10 in.) apart, perpendicular to the yarn beingtested and extending 25 mm (1 in.) into the fabric, and recordthe distance between bench marks as di
29、stance (F) (in-fabricdistance).10.4.1 If a direct reading device is used, follow the manu-facturers recommendations for establishing the specimenlength.10.5 Prepare an edge by making a cut at least 350 mm (14in.) long, parallel, and in the direction of the yarn to bemeasured, and such that it crosse
30、s near the ends of both linesof the bench mark.10.6 Ravel several yarns from the cut edge, such that theycontain the bench marks.10.7 One at a time, when ready to use, ravel ten yarnspecimens from the prepared edge of the fabric. Ensure that thebench marks appear on each yarn. Take care not to distu
31、rb thetwist or strain the yarn. Maintain identity of the fabric directionbeing evaluated, that is, warpwise or fillingwise.10.8 Fasten one of the yarn specimens in the clamps of atensioning device or, if applicable, in the proper position of theyarn supports of a direct reading crimp tester with the
32、 benchmarks coincident with the nips of the respective clamps that areset for the initial in-fabric length.10.8.1 Clamp type devices may consist of a twist counterfitted with graduated sliding clamp, or a tension testingmachine or which the movement or action can be stoppedinstantly at any point, su
33、ch as the constant-rate-of-elongation(CRE-Type) or other similar instrument. For a direct readingcrimp tester, the yarn is placed under the hook of the movableshaft with the bench marks on the yarn aligned with the upperfixed yarn supports.10.9 Apply a force to the yarn just sufficient to removeundu
34、lations due to weaving, without imparting stretch asdetermined by using one of the following three options.NOTE 1The three options can give different results. For maximumprecision between laboratories, it is recommended that the laboratories usethe same equipment and the same option.10.9.1 Option A,
35、 By HandStraighten the yarn by handagainst a scale graduated in 1 mm (116 in.), observe and record3Commercially available devices that have been found acceptable are a twisttester with tension device, a tensile testing machine, and a crimp tester of the directreading type.D3883042the distance betwee
36、n bench marks to the nearest 1 mm (116 in.)as (Y) (straightened yarn distance).NOTE 2This is the least accurate option because the tension requiredto remove crimp is unknown.10.9.2 Option B, by Tension Device or Crimp TesterUsingone of the tensioning devices or crimp tester, apply a tensionforce bas
37、ed upon the known yarn size. If the tension force isnot sufficient to remove all the crimp, gradually increase thetension force until the crimp just removed. Use the determinedforce on all the yarns in the set and proportional force on anyother samples in the series or test.10.9.2.1 Estimate the req
38、uired tension force using Eq 1:Tensile force, g 5 yarn number in tex 3 0.25 (1)10.9.3 Option C, Tensile Testing MachineUsing aconstant-rate-of-extension (CRE-type) of testing machine, de-termine the force to remove undulations by analysis of aforce-extension as described in 10.9.3.1.10.9.3.1 Establi
39、sh Point A as the point where the force-extension curve begins, that is, zero force and zero extension.Extrapolate the straight-line portion of the force-extensioncurve through the extension axis, Line CE. The portion of thecurveAD represents the removal of the crimp and initial stretchof the yarn.
40、Establish Point D where the force-extension curveseparates from the line CE. Establish Point B by constructinga line from Point C, parallel to the force axis to curve AD.Establish Point L by constructing a line from Point B throughthe force axis, parallel to the extension axis. The forcecorrespondin
41、g to Point L is the required tensile force to removethe crimp without stretching (see Fig. 1).10.10 Determine and record the length of the yarn to thenearest 2.5 mm (0.1 in.) after removal of the crimp as follows:10.10.1 For clamp-type devices, measure the distance be-tween the bench marks on the st
42、raightened yarn and record asdistance (Y) (straightened yarn distance).10.10.2 For constant-rate-of-extension machines, determineand record the straightened distance (Y) between bench marksdirectly from the extension axis of the force-extension curveillustrated on Fig. 1 by line LB, projected to the
43、 extension axis,allowing for any chart magnification ratio.10.10.2.1 For some tensile testers, straightened yarn dis-tance (Y) and the percent yarn crimp or yarn take-up can becomputer-processed automatically.10.10.3 For direct-reading crimp testers, read the yarn crimpor yarn take-up directly from
44、the dial or scale.11. Calculation11.1 Calculate the average distance between the two benchmarks on the straightened yarn for all measured specimens tothe nearest 2.5 mm (0.1 in.), for each warpwise direction andfillingwise direction, as applicable.11.2 Calculate the average yarn crimp or average yar
45、ntake-up to the nearest 0.1 % using Eq 2 or Eq 3, for eachwarpwise direction and fillingwise direction, as applicable:C 5 100Y2F!/F (2)T 5 100Y2F!/Y (3)where:C = yarn crimp, %,T = yarn take-up, %,F = average of distances between bench marks on yarn infabric, mm (in.) (from 10.4), andY = average of d
46、istances between bench marks on yarnafter removal from fabric and straightened under ten-sion, mm (in.) (from 10.10).11.2.1 When data are computer-processed automatically,calculations generally are contained in the associated software.It is recommended that computer processed data be verifiedagainst
47、 known property values and its software described in thereport.11.2.2 For direct-reading crimp testers, the yarn crimp oryarn take-up is read directly from the dial or scale.12. Report12.1 The report shall contain the following information:12.1.1 Report that the yarn crimp and yarn take-up wasdeterm
48、ined as directed in Test Method D 3883. Describe thematerial or product sampled and the method of sampling used.12.1.2 Report the following information for the warpwiseand fillingwise directions for the laboratory sampling unit andfor the lot as applicable to a material specification or contractorde
49、r.12.1.2.1 Average yarn crimp and average yarn take-up;12.1.2.2 Test option, manufacturer, and model of test instru-ment;12.1.2.3 Force used to remove crimp;FIG. 1 Example Chart For Determining of Tensile Force UsingOption CD388304312.1.2.4 When calculated, the standard deviation or thecoefficient of variation.12.1.2.5 For computer-processed data, identify the program(software) used.13. Precision and Bias13.1 Interlaboratory Test Data4An interlaboratory testwas run in 1972 in which randomly-drawn samples of threematerials were tested in each of three laboratories. Oneo